Conventional light source for film scanner generally does not fully utilize the energy available. In this age of energy saving, it is important to provide an efficient light source.
FIG. 5 shows a design of the light source disclosed in Patent No. 309104 of the Republic of China in Taiwan. The light source is composed of a straight light tube 21, an arc-shaped cover 22 and a reflecting plate 23. A drawback of this design is that the arc-shaped cover blocks most of the light emitted from the light source. Only 1/5 to 1/6 of the light is utilized, thus wasting a great deal of energy.